- Top of Page
The invention relates to a medicament administration device comprising a rigid medicament container for a liquid medicament with an outlet for the medicament.
- Top of Page
OF THE INVENTION
Many medicaments have to be injected into the body. This applies in particular to medicaments, which are deactivated or have their efficiency remarkably decreased by oral administration, e.g. proteines (such as insulin, growth hormones, interferons), carbohydrates (e.g. heparin), antibodies and the majority of vaccines. Such medicaments are predominantly injected by means of syringes, medicament pens or medicament pumps.
Some medicaments have to be administered by inhaling them from so called inhalers.
U.S. Pat. No. 4,313,439 A discloses a system for the administration of a medicament to a patient in small, controlled doses over an extended period in response to a continuously generated force. The force may be maintained continuously on a reservoir of the medicament in intermittent communication with a site in the body of the patient through a flexible and compressible tube. Alternatively the force may be applied intermittently to the reservoir through the action of an escapement mechanism.
U.S. Pat. No. 4,424,057 A discloses a wet-dry syringe for combining and mixing a liquid and a solid medicament or at least two dissimilar liquid medicaments prior to the application thereof to a patient. The syringe comprises a first vial containing a liquid or solid medicament and a second vial containing a liquid medicament. The second vial has an end seal including a hollow piercing needle to pierce a first end seal of the first vial causing medicament to flow from the second vial into the first vial thereby mixing the medicaments prior to application to a patient by means of a needle piecing assembly which pierces a second end seal of the first vial and a patient. The second vial functions as a piston rod and aids in the discharge of the medicaments.
- Top of Page
OF THE INVENTION
It is an object of the present invention to provide an improved medicament administration device.
The object is achieved by a medicament administration device according to claim 1.
Preferred embodiments of the invention are given in the dependent claims.
A medicament administration device according to the invention comprises a rigid medicament container for a liquid medicament with an outlet for the medicament and a storage means for storing solid particles. In addition it comprises a feeding means for feeding solid particles from the storage means into the medicament container to displace a dose of medicament by solid particles, thereby squeezing the dose of medicament through the outlet of the medicament container.
The storage means and the feeding means allow for dispensing a dose of medicament by displacing the dose by solid particles. In this way the medicament can be dosed very accurately by feeding a definite amount of solid particles into the medicament container.
In a preferred embodiment of the medicament administration device the solid particles are incompressible. This allows for an easy medicament dosing as the incompressibility of the solid particles implies that the total volume of the solid particles fed into the medicament container determines directly the dose of medicament displaced by these solid particles. In particular, using solid particles of equal definite volume, the number of solid particles fed into the medicament container is directly proportional to the dose of medicament displaced by these solid particles.
Preferably the solid particles consist of a material which is inert to chemical reactions with the liquid medicament. This avoids advantageously that the chemical structure of the medicament is affected by the solid particles fed into the medicament container. In particular there is no need to separate the solid particles from the medicament, in contrast to other displacement media such as media used with hydraulic systems. Furthermore chemically inert materials avoid that the volume of the solid particles fed into the medicament container is affected by chemical reactions with the medicament and thus that the dose of medicament displaced by solid particles is affected by such chemical reactions.
In particular the solid particles may consist of glass and/or a rubber material and/or polytetrafluoroethylene. These materials are chemically inert to chemical reactions with many medicaments and are therefore appropriate to a number of medicaments.
Furthermore the solid particles may be ball-shaped or cubical-shaped. This has the advantage that the total volume of solid particles fed into the medicament container can be easily determined from their number and thus allows for an easy medicament dosing. Furthermore ball-shaped or cubical-shaped solid particles do not easily get stuck, in contrast to solid particles with a more complicated shape which may cause catching or jamming of solid particles. Hence ball-shaped or cubical-shaped particles can be more easily stored and fed into the medicament container than solid particles with a more complicated shape.
Preferably the storage means comprises subunits for storing separately portions of solid particles. This allows for preparing medicament doses by correspondingly sizing the subunits. E.g., one may use subunits of equal size that corresponds to a minimum medicament dose to be dispensed, or a fraction thereof. Alternatively one may use subunits of different size such that any needed dose corresponds to a combination of subunits.
The feeding means may comprise a piston to press solid particles out of the storage means. Furthermore the feeding means may comprise connection means connecting the storage means and the medicament container to feed solid particles from the storage means into the medicament container. This allows to feed solid particles into the medicament container through the connection means by using the piston to exert pressure to the storage means.
Preferably the medicament administration device comprises a restraining means to prevent solid particles from leaving the medicament container. The restraining means may comprise a filter for the outlet of the medicament container, the filter being impenetrable for the solid particles. Such a restraining means avoids advantageously that solid particles are dispensed together with a medicament dose. Alternatively, one may use a physical separation method, based, for instance, on a gravitational of centrifugal force, to prevent solid particles from leaving the medicament container.
The medicament container may be part of an injection arrangement or an inhaler arrangement for delivering a liquid medicament to a human or an animal.
The injection arrangement may comprise a valve and a hollow needle for piercing a patient\'s skin, the valve and needle being arranged at the outlet of the medicament container. In that case the outlet of the medicament container may comprise an interface for receiving a hollow injection needle. Alternatively, the needle may be integrated with the medicament container. In case of a jet injector, instead of the needle, a jet nozzle may be arranged.
The medicament container may preferably be used for delivering one of an analgesic, an anticoagulant, insulin, insulin derivate, heparin, Lovenox, a vaccine, a growth hormone, a peptide hormone, a protein, antibodies and complex carbohydrates.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only.
BRIEF DESCRIPTION OF THE DRAWINGS
- Top of Page
The present invention will become more fully understood from the detailed description given hereinbelow and an accompanying drawing which is given by way of illustration only, and thus is not limitive of the present invention, and wherein:
FIG. 1 illustrates a medicament administration device comprising a medicament container and storage means from which solid particles are fed into the medicament container.
- Top of Page
OF PREFERRED EMBODIMENTS
FIG. 1 illustrates a medicament administration device 1 according to the invention which is part of an injection arrangement I for delivering a liquid medicament. The medicament administration device 1 comprises a rigid medicament container 2 with an outlet 3 for the liquid medicament and a storage means 4 from which solid particles 5 are fed into the medicament container 2. The storage means 4 comprises subunits 6 for storing separately portions of solid particles 5.
The medicament administration device 1 further comprises a filter 7 covering the outlet 3 of the medicament container 2. The filter 7 is penetrable for the liquid medicament, but impenetrable for the solid particles 5. The filter 7 thus restrains the solid particles 5 from leaving the medicament container 2.
The injection arrangement I further comprises a hollow needle 8 for piercing a patient\'s skin. The needle 8 is connected to the outlet 3 so that the liquid medicament can flow from the interior of the medicament container 2 through the outlet 3 to the needle 8. The injection arrangement I further comprises an interface 9 for attaching the needle 8 to the outlet 3.
Alternatively the medicament injection arrangement I may be designed as a jet injector having a jet nozzle instead of a needle 8.